Early in his career Nelson did stunt work for B-movie producer Roger Corman on the films Swamp Women (1956), Attack of the Crab Monsters (1957), Rock All Night (1957), Carnival Rock (1957), Night of the Blood Beast (1958), The Cry Baby Killer (1958), Teenage Cave Man (1958), and A Bucket of Blood (1959). Also in 1958 he acted in and produced actor-director Bruno VeSota’s science fiction horror film The Brain Eaters, which Roger Corman executive produced. That same year he was cast as the lead in Devil’s Partner, though the film was not released until 1962. He also appeared in the 1960 thriller Valley of the Redwoods and the 1963 comedy drama Soldier in the Rain, starring Steve McQueen and Jackie Gleason.

He made two guest appearances on CBS’s Perry Mason, both times as the defendant; in 1961, he played Ward Nichols in “The Case of the Left-Handed Liar,” and in 1964, he played Dirk Blake, father of the title character, in “The Case of the Missing Button”.

Nelson’s television career featured many guest starring roles, such as the talented but arrogant Dr. Wade Parsons in the 1962 episode “Doctor on Horseback” of the NBC western series, The Tall Man, starring Barry Sullivan as Sheriff Pat Garrett and Clu Gulager as Billy the Kid. In the story line Dr. Parsons works to save the life of a pregnant young woman who attempts suicide when her husband deserts her.

After Peyton Place, Nelson worked in many more productions of all varieties. He teamed with former Peyton Place co-star Percy Rodriguez in a second television series, The Silent Force, which ran for 15 episodes in 1970-1971. He had guest starred with David Janssen in The Fugitive in 1963, and appeared as a different character later in the series. Subsequently, Nelson had guest starring roles on many of the popular dramas of the 1970s and 1980s, including Marcus Welby, M.D., Cannon, O’Hara, U.S. Treasury, Night Gallery, Banacek, Alias Smith and Jones, Mod Squad, Mission: Impossible, The Streets of San Francisco, Kung Fu, The F.B.I. (in 3 different roles), Adam-12, Ironside, Police Woman, Medical Center (3 roles), The Bionic Woman, Gibbsville, McMillan and Wife, Dallas, The Rockford Files (2 roles), Barnaby Jones (2 roles), Charlie’s Angels, Lou Grant, Trapper John, M.D., Vega$ (2 roles), CHiPs, Quincy M.E., Matt Houston, The Fall Guy, Dynasty, Cagney & Lacey, MacGyver, Jake and the Fatman (2 roles), and Murder, She Wrote (5 roles).

In 1964, Nelson secured his most famous role, portraying Dr. Michael Rossi on the ABC drama Peyton Place, staying with the series during its entire run from 1964 to 1969. Nelson reprised his role in two made-for-TV movies, Murder in Peyton Place and Peyton Place: The Next Generation.

Nelson appeared in many television movies such as Along Came a Spider (1970), The Screaming Woman (1972), Runaway! (1973), Houston, We’ve Got a Problem (1974), The Missing Are Deadly (1975), Superdome (1978), Doctors’ Private Lives (1978) and Crash (1978), and served as host on a morning talk show, The Ed Nelson Show, that he hosted for three years. During the 1980s, Nelson took on the role of patriarchal Senator Mark Denning in the daytime serial Capitol. In late 1986, Nelson was upset to discover that the show’s writers had turned his character into a traitor, and quit the show in disgust, last airing in early January 1987, two months prior to the show’s cancellation.

In 1999, Nelson returned to Tulane University to finish credits toward his undergraduate degree, which he completed the following year at age 71. He and his wife, Patsy, enjoyed semi-retirement visiting their six children and fourteen grandchildren. One of his children is actor Christopher S. Nelson.

Until 2005, he had been teaching acting and screenwriting in New Orleans at two local universities there. Hurricane Katrina prompted him to move his family far to the north to Sterlington, Louisiana. At the time of his death, however, he had relocated to Greensboro, North Carolina, where he had been in hospice care. He died at age 85.

Nelson died on August 9, 2014, in Greensboro, North Carolina, from congestive heart failure. He was 85 years old.